Questions tagged [hall-effect]
The Hall effect is a voltage arising from an electric field perpendicular to a magnetic field in a material. It is to be distinguished from the quantum hall effect (QHE).
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Deriving classical Hall effect from quantum Hall effect
I'm interested in the derivation of the classical Hall effect coefficient, given in cgs by $$R_{H}=-\frac{1}{nec},$$ where $n$ is the electron number density, $-e<0$ is the electron charge,and $c$ ...
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Does the Hall effect increase the resistance of a wire?
If a current in a wire is flowing perpendicular to a magnetic field, the Hall effect is observed. This effect is caused by the forces from magnetic fields pushing the electrons to one side of the wire....
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How can we explain that beryllium has positive charge carriers as a metal (from Feynman Lectures)?
This question naturally arises from reading Feynman Lectures Vol III 14-3 The Hall effect, online available here, where Feynman states the following:
The original discovery of the anomalous sign of ...
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Hall effect for a magnet falling through a copper pipe?
A falling magnet in a copper pipe exerts a Lorentz force on the electrons that participate in the eddy currents a and b. I mean the vertical magnetic force $F = Bqv$, denoted by the blue arrows in the ...
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Why are the plateaus in the Quantum Hall horizontal rather than diagonal
I was wondering why the plateaus of $\rho_{xy}$ in the integer quantum Hall effect are horizontal and do not scale linearly with the magnetic field $B$ since the Lorentz force should still be acting ...
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Shubnikov-de-Haas effect and Quantum Hall effect
I am wondering if these two phenomena are two names for the same thing or whether these are distinct effects and there are situation where one appears, but the other one doesn't?
Both seem to produce ...
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Longitudinal conductivity from density of states (DOS)
It is well-known that using the so-called Streda formula, the transversal conductivity $\sigma_{xy}$ and thus the Hall conductivity in a two-dimensional material is given as the derivative of the ...
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What does it mean to say that the majority carriers are holes?
Even when there are holes, the holes move only because electrons are jumping from one hole to the next. So why doesn't it make sense to say that electrons are the majority carriers in p-type ...
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Why (intuitively) do more charge carriers result in a smaller Hall effect?
From the equation for the Hall effect:
$$\Delta V_H= \frac{I B}{n q t}$$
[Where $I$ is the current, $B$ the electric field magnitude, $n$ the density of charge carriers, $q$ the charge per charge ...
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Impact of thickness of metal on hall effect
I was reading the paper on the Hall Effect and found that the initial experiment was performed on a metal strip. The experiment on the metal failed to provide any useful results, and then it was ...
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Is current density independent of applied fields for Bloch electrons?
Following Ashcroft-Mermin chapter 12 the semiclassical dynamics is governed by
$
\dot{\vec{r}} = \vec{v}_n(\vec{k}) = \frac{1}{\hbar}\frac{\partial \epsilon_n(\vec{k})}{\partial \vec{k}}
$
and
$
\hbar ...
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How do protons and electrons separate across a conductor in the Hall Effect, if protons "don't move"?
I have a (probably very) basic understanding of electricity, how/why current flows, etc. from my ham technician's license. I often think of the water-in-a-hose analogy, how pressure (voltage?) causes ...
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Charge carriers type: contradiction between Hall effect and Seebeck effect, how to resolve it?
On one hand the Hall effect consists of a voltage that arises when an electric field and a perpendicular magnetic field are in a material. This makes the charge carriers (electrons or holes) under the ...
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Variation of Current In The Hall Effect Experiment
As a 12th Grader, our class came across a very simple setup of the Hall Effect Experiment during our course on Electromagnetism. The entire idea and eventual steady state conditions all make perfect ...
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Are anomalous Hall effect and spin Hall effect mutually exclusive?
In many papers that cover an analysis of Hall effects, the spin Hall effect is often qualitatively described as being nearly the same as the anomalous Hall effect except for the fact that it doesn't ...
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